NSX 2.0 new exhausts

Aftermarket exhausts for the new NSX seem to be popping up with regularity now. I seem to get fairly excited to hear one and then get surprised with how muted the turbos make the engine note. Even the few that have been recorded don't sound much different than stock. Certainly nothing like a 488 GTB.

Nothing more known about this Heffner system other than it's their own proprietary design.